# uncompyle6 version 3.2.3
# Python bytecode 3.6 (3379)
# Decompiled from: Python 3.6.8 |Anaconda custom (64-bit)| (default, Feb 21 2019, 18:30:04) [MSC v.1916 64 bit (AMD64)]
# Embedded file name: site-packages\cryptography\hazmat\backends\openssl\utils.py
from __future__ import absolute_import, division, print_function
import warnings
from cryptography import utils
from cryptography.hazmat.primitives import hashes
from cryptography.hazmat.primitives.asymmetric.utils import Prehashed


def _calculate_digest_and_algorithm(backend, data, algorithm):
    if not isinstance(algorithm, Prehashed):
        hash_ctx = hashes.Hash(algorithm, backend)
        hash_ctx.update(data)
        data = hash_ctx.finalize()
    else:
        algorithm = algorithm._algorithm
    if len(data) != algorithm.digest_size:
        raise ValueError(
            "The provided data must be the same length as the hash algorithm's digest size."
        )
    return (data, algorithm)


def _check_not_prehashed(signature_algorithm):
    if isinstance(signature_algorithm, Prehashed):
        raise TypeError(
            "Prehashed is only supported in the sign and verify methods. It cannot be used with signer or verifier."
        )


def _warn_sign_verify_deprecated():
    warnings.warn(
        "signer and verifier have been deprecated. Please use sign and verify instead.",
        utils.PersistentlyDeprecated,
        stacklevel=3,
    )
